Reversible acute renal failure in idiopathic nephrotic syndrome.

Acute renal insufficiency developed in four idiopathic nephrotic patients with minimal change or mild proliferative glomerulonephritis. The reduction in glomerular filtration rate (CInulin) was not in proportion to the renal plasma flow (CPAH) as evidenced by a low filtration fraction. Diuretic therapy failed to reverse renal insufficiency, and renal biopsy showed no evidence of interstitial nephritis, acute tubular necrosis or interstitial edema. Corticosteroid therapy induced a recovery of renal function with a decrease in proteinuria. These observations suggest that acute renal insufficiency in the idiopathic nephrotic syndrome might be caused by impaired glomerular permeability.